The world party for space once again celebrates the anniversary of the first human spaceflight. Our guests are Yuri’s Night founders Loretta and George Whitesides. George is also President and CEO of Virgin Galactic, now preparing SpaceShipTwo for its first powered flight. They are joined by Bobak Ferdowsi, JPL’s famous “Mohawk Guy,” flight director for Curiosity, the Mars Science Laboratory Rover. You’ll also hear Emily Lakdawalla on why this is the golden age of space exploration. Bruce Betts reports from the Planetary Defense Conference in Arizona. Bill Nye returns next week.